# Usage

Usage examples for SendGrid REST library

## Initialization

```go

package main

import (

	"encoding/json"

	"fmt"

	"os"

	"github.com/sendgrid/rest"

)

// Build the URL

const host = "https://api.sendgrid.com"

endpoint := "/v3/api_keys"

baseURL := host + endpoint

// Build the request headers

key := os.Getenv("SENDGRID_API_KEY")

Headers := make(map[string]string)

Headers["Authorization"] = "Bearer " + key

```

## Table of Contents

- [GET](#get)

- [DELETE](#delete)

- [POST](#post)

- [PUT](#put)

- [PATCH](#patch)

<a name="get"></a>

## GET

#### GET Single

```go

method = rest.Get

// Make the API call

request = rest.Request{

    Method:  method,

    BaseURL: baseURL + "/" + apiKey,

    Headers: Headers,

}

response, err = rest.API(request)

if err != nil {

    fmt.Println(err)

} else {

    fmt.Println(response.StatusCode)

    fmt.Println(response.Body)

    fmt.Println(response.Headers)

}

```

#### GET Collection

```go

method := rest.Get

// Build the query parameters

queryParams := make(map[string]string)

queryParams["limit"] = "100"

queryParams["offset"] = "0"

// Make the API call

request := rest.Request{

    Method:      method,

    BaseURL:     baseURL,

    Headers:     Headers,

    QueryParams: queryParams,

}

response, err := rest.API(request)

if err != nil {

    fmt.Println(err)

} else {

    fmt.Println(response.StatusCode)

    fmt.Println(response.Body)

    fmt.Println(response.Headers)

}

```

<a name="delete"></a>

## DELETE

```go

method = rest.Delete

// Make the API call

request = rest.Request{

	Method:      method,

	BaseURL:     baseURL + "/" + apiKey,

	Headers:     Headers,

	QueryParams: queryParams,

}

response, err = rest.API(request)

if err != nil {

	fmt.Println(err)

} else {

	fmt.Println(response.StatusCode)

	fmt.Println(response.Headers)

}

```

<a name="post"></a>

## POST

```go

method = rest.Post

// Build the request body

var Body = []byte(`{

    "name": "My API Key",

    "scopes": [

        "mail.send",

        "alerts.create",

        "alerts.read"

    ]

}`)

// Make the API call

request = rest.Request{

	Method:      method,

	BaseURL:     baseURL,

	Headers:     Headers,

	QueryParams: queryParams,

	Body:        Body,

}

response, err = rest.API(request)

if err != nil {

	fmt.Println(err)

} else {

	fmt.Println(response.StatusCode)

	fmt.Println(response.Body)

	fmt.Println(response.Headers)

}

// Get a particular return value.

// Note that you can unmarshall into a struct if

// you know the JSON structure in advance.

b := []byte(response.Body)

var f interface{}

err = json.Unmarshal(b, &f)

if err != nil {

	fmt.Println(err)

}

m := f.(map[string]interface{})

apiKey := m["api_key_id"].(string)

```

<a name="put"></a>

## PUT

```go

method = rest.Put

// Build the request body

Body = []byte(`{

    "name": "A New Hope",

    "scopes": [

        "user.profile.read",

        "user.profile.update"

    ]

}`)

// Make the API call

request = rest.Request{

	Method:  method,

	BaseURL: baseURL + "/" + apiKey,

	Headers: Headers,

	Body:    Body,

}

response, err = rest.API(request)

if err != nil {

	fmt.Println(err)

} else {

	fmt.Println(response.StatusCode)

	fmt.Println(response.Body)

	fmt.Println(response.Headers)

}

```

<a name="patch"></a>

## PATCH

```go

method = rest.Patch

// Build the request body

Body = []byte(`{

    "name": "A New Hope"

}`)

// Make the API call

request = rest.Request{

	Method:  method,

	BaseURL: baseURL + "/" + apiKey,

	Headers: Headers,

	Body:    Body,

}

response, err = rest.API(request)

if err != nil {

	fmt.Println(err)

} else {

	fmt.Println(response.StatusCode)

	fmt.Println(response.Body)

	fmt.Println(response.Headers)

}

```